This Background is intended to provide the basic context of this patent application and is not intended to describe a specific problem to be solved.
Computer monitors emit color within a color space comprising RGB (red, green, blue) light. Although all colors of the visible spectrum can be produced by merging red, green and blue light, monitors are capable of displaying only a limited gamut (i.e., range) of the visible spectrum. Each pixel presented in the RGB format will include a separate value within a range of 0 to 255 for each of R, G, and B to produce a pixel. However, computers may also emit color within a variety of other color spaces. For example, another color space may comprise data consisting of luminance (Y), chrominance of the blue to yellow color content (U or Cb), and chrominance of the red to cyan color content (V or Cr). As with RGB, pixels in the YUV format are also comprised of separate values for each of Y, U, and V. However, the ranges for each value of R, G, and B do not correspond directly to the ranges for Y, U, and V. For example, in one YUV format, the range of values for Y is 16 to 235, while the ranges for both U and V is 16 to 239. Therefore, for a computer to properly display YUV video content in RGB, the YUV values for each pixel must be converted to corresponding RGB values.
Present methods for conversion from one video format to another are computationally expensive and may require the processing of input data through a matrix transform to produce output. To convert from YUV to RGB, data from each pixel must be processed through a matrix transform with 7 multiplication and 11 add/subtract operations. In practice, a compiler may reduce the common sub-expressions of matrix transforms. For example, the matrix transform to convert YUV to RGB may be readily reduced to 5 multiplication and 7 add/subtract operations. However, even a compiler-reduced matrix transform is computationally expensive. Due to the complexity of pixel conversion, the process typically requires extensive support to include Single Instruction, Multiple Data (SIMD) parallel processing extensions for execution within a useful time. Further, computers that are unable to implement SIMD extensions are unable to easily perform pixel conversion.